The project aims at exploiting those changes in cell surface which accompany neoplastic transformation with the object of finding cell division inhibitors which selectively bind to transformed cells. In the case of manifest cancer, the immune response evoked by the malignant cells have failed to effect a complete rejection of the neoplastic cells. Studies are carried out with the aim of increasing the immunogenicity of the neoplastic cells and preventing some aspects of enhancement. Application of cell surface molecules to cultured human cells is immediately relevant to clinical chemotherapy. To this end efforts were made to maintain human tumors in long term culture.